JP2015221021A - Method and apparatus for producing feed additive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for producing a feed additive, in which animalcules can be stably cultured and obtained as raw material of the feed additive, even if raw water has heavy load or load fluctuation is large.SOLUTION: The method for producing a feed additive by a main treatment apparatus 2 comprises: a first biological treatment step of introducing organic waste water to a first biological treatment tank 10 and performing aerobic bacterial treatment by bacteria to obtain first biological treatment liquid containing dispersible bacteria; a second biological treatment step of introducing the first biological treatment liquid to a second biological treatment tank 20 and performing activated sludge treatment to obtain second biological treatment liquid; and a sludge separation step of taking out a part of in-tank sludge in the second biological treatment tank to obtain it as raw material of the feed additive; wherein at least a part of the organic waste water is supplied and subjected to treatment to a sub treatment apparatus 3 so that the load of the first biological treatment tank 10 is not greater than prescribed load.

Description

  The present invention relates to a method and an apparatus for efficiently producing a feed additive for use in livestock and fisheries using organic waste water.

  With the depletion of natural resources around the world, animal protein such as fish meal, which is a feed material for aquaculture, is decreasing and its price is also rising. Plant-based alternative proteins are being used, but there are problems such as low digestibility and palatability, resulting in low feed efficiency, and there is a need for inexpensive animal proteins.

  Rotifer is widely used as an animal feed for production of inoculum of marine fish. As a method for cultivating rotifers, Patent Document 1 (Japanese Patent Laid-Open No. 57-65137) describes culturing rotifers by flowing down biologically treated sludge from organic wastewater such as food processing wastewater. Patent Document 2 (Japanese Patent Application Laid-Open No. 2006-247494) describes that organic waste water is subjected to an aerobic biological treatment in a dispersible bacteria production tank and a subsequent minute animal treatment tank.

  By treating organic wastewater in a dispersible bacteria production tank and a micro-animal culture tank to produce surplus sludge with a high content of micro-animals and using this as an additive for feed, so that the micro-animals can efficiently grow The residence time and DO (dissolved oxygen) of the dispersible bacteria production tank are adjusted, and the BOD / sludge load and SRT (sludge residence time) of the micro animal culture tank are adjusted. However, when wastewater with large load fluctuations such as food wastewater and sewage are targeted as raw water, the concentration and water volume change greatly, and both the conditions of the dispersive bacteria production tank and the conditions of the micro-animal culture tank are optimally maintained. It was extremely difficult. For this reason, the number of micro-animals to be cultured may change greatly, and the quality of the feed additive produced may also change greatly.

JP-A-57-65137 JP 2006-247494 A

  An object of the present invention is to provide a method and an apparatus for producing an additive for feed that can be obtained as a feed additive by stably cultivating a micro animal even when the load fluctuation of raw water is large. .

  The method for producing an additive for feed according to the present invention is a first biological treatment in which organic waste water is introduced into a first biological treatment tank and an aerobic biological treatment is performed with bacteria to obtain a first biological treatment liquid containing dispersible bacteria. A step, a second biological treatment step of introducing the first biological treatment liquid into the second biological treatment tank and treating the activated sludge to obtain a second biological treatment liquid, and a part of the sludge in the tank of the second biological treatment tank In a method for producing a feed additive by a main treatment step having a sludge separation step to be taken out and obtained as a raw material for the feed additive, the organic waste water is discharged so that the tank load of the first biological treatment tank is within a predetermined range. At least a part is supplied to the sub-process and processed.

  The feed additive production apparatus of the present invention includes a first biological treatment tank that receives an organic wastewater and aerobic biological treatment with bacteria to obtain a first biological treatment liquid containing dispersible bacteria, and a first biological treatment liquid A second biological treatment tank that receives activated sludge and obtains a second biological treatment liquid, and a sludge separation means that extracts a portion of the sludge in the tank of the second biological treatment tank and obtains it as an additive for feed An apparatus for producing an additive for feed by a processing apparatus, comprising: a sub-processing apparatus that receives and processes at least a part of organic waste water so that the tank load of the first biological treatment tank falls within a predetermined range. It is what.

It is preferable that the tank load of a 1st biological treatment tank is the load range selected from 2-30 kg-BOD / m < ³ > / day.

It is preferable that SRT of a 2nd biological treatment tank is 10 to 40 days, and tank load is 1-5 kg-BOD / m < ³ > / day with respect to the raw | natural water of a main processing apparatus entrance.

  In this invention, you may provide the pre-processing means for removing the solid content and / or oil content in organic waste water in the front | former stage of a 1st biological treatment tank.

In the present invention, the sub-treatment step is an aerobic biological treatment using a fixed bed, and the tank load is preferably 1 to 5 kg-BOD / m ³ / day or less.

In the method and apparatus for producing a feed additive of the present invention, the tank load of the first biological treatment tank in the main treatment step (main treatment apparatus) for producing the feed additive is 2 to 30 kg-BOD / m ³ / day. When the load exceeds a certain load selected from the range, the portion of the organic waste water exceeding the predetermined range is processed in another sub-processing step (sub-processing device). As a result, even if there is a fluctuation in the raw water load, it is possible to stably culture micro-animals in the main treatment process, and it is possible to produce feed additives. In addition, even when the water temperature changes in summer and winter, the conditions of the second biological treatment tank for producing minute animals can be optimally maintained.

It is a flowchart of the cultivation method and apparatus of the additive for feed which concern on embodiment. It is a flowchart of the cultivation method and apparatus of the additive for feed concerning a comparative example.

  In the present invention, as shown in FIG. 1, organic wastewater is pretreated by pretreatment means 1 installed as necessary, and after removing solids and oils, the organic wastewater is introduced into the main treatment device 2 and treated. When the load of the effluent is large, at least a part of the organic effluent is supplied to the sub-processing device 3 for processing. The preprocessing unit 1 may be omitted.

  In the main treatment apparatus 2, organic wastewater is aerobically treated in a first biological treatment tank (biological treatment tank) 10 to culture bacteria, and the first treated water from the first biological treatment tank 10 is used as the first treatment water. 2 The microanimal is cultured by introducing it into the biological treatment tank (biological treatment tank) 20 and allowing the microanimals (protozoa, metazoans) to prey on the dispersal bacteria contained in the first treated water. In FIG. 1, the 2nd treated water from this 2nd biological treatment tank 20 is introduce | transduced into the precipitation tank 30, and it separates into solid and liquid, and takes out treated water out of the system.

  Part of the sludge in the second biological treatment tank 20 and the sludge settled in the settling tank 30 are introduced into the concentration tank 40. A first filter medium 41 having a large mesh and a second filter medium 42 having a small mesh are provided in the concentration tank 40, and passes through the first filter medium 41, and the second filter medium 42. Harvested metazoans and sludge of a size that does not pass through as feed additives or their raw materials.

  Although the sub-processing apparatus 3 has the aerobic biological treatment tank 51 provided with the diffuser pipe 51a and the sedimentation tank 52, it is not limited to this. The aerobic biological treatment tank 51 may be provided with a fixed bed.

<Organic drainage>
Organic wastewater includes food factory wastewater (for example, boiled juice from a food factory), fish meal dispersion water, livestock wastewater, blood wastewater, rice powder wastewater, and other cereal powder dispersion water, crushed food wastewater, waste milk, waste Examples include beverages, supplement production wastewater, feed production plant wastewater, sewage and the like. This organic waste water may contain 10 wt% or more, for example, 20 to 40 wt% of the total sugar and / or crude fat. These components are necessary for the growth of the microanimal.

<Pretreatment means>
The pretreatment means 1 is preferably used in the case where solid matter, oil, or the like that affects the operating conditions of the biological treatment tanks 10 and 20 in the subsequent stages are contained in the waste water. As a means for removing the solid matter from the organic waste water, a screen, a solid matter precipitation tank, or the like can be used. As the oil removing means, a pressure floating type separation device or the like can be used. Both solids removal means and oil content removal means may be used.

<First biological treatment tank>
The organic waste water from the pretreatment means 1 is passed through the first biological treatment tank 10 in a transient manner, preferably with a residence time of 2 to 15 hours, and BOD components (organic components) are removed by bacteria. Convert to body (fungal culture).

  In the first biological treatment tank 10, bacteria serving as food for minute animals such as rotifers are cultured. Bacteria that serve as food for micro-animals such as rotifers are preferably those that form micro flocs of about 3 to 10 μm, particularly 5 to 10 μm, and are rich in proteins and carbohydrates.

  Such micro floc dispersible bacteria can be obtained by continuously culturing under aerobic conditions with a residence time of about 2 to 10 hours using a substrate containing protein and carbohydrate, preferably a soluble polymer compound as a substrate. . As the first biological treatment tank 10, a tank having a DO concentration of less than 1 mg / L may be used. As shown in FIG. 1, it is desirable to provide a stirrer 1a in the first biological treatment tank 10 and vigorously stir to suppress the dispersible bacteria from becoming coarse floc.

  The pH of the first biological treatment tank 10 is preferably 5 to 9, and when the substrate contains oil, it is slightly higher, specifically about 8 to 9 is preferable.

  As described above, the residence time of the first biological treatment tank 10 is preferably 2 to 15 hours. However, when soluble soluble starch, fish meat extract or the like is used as the organic waste water, it is about 2 to 8 hours. In the case of using a solid material, about 6 to 15 hours is preferable.

  Although the temperature of the 1st biological treatment tank 10 has preferable 25-35 degreeC, it should just be the range of 10-40 degreeC.

  By culturing bacteria under such conditions, 40-70% of the weight of organic matter in the input organic wastewater, for example, approximately 50%, continuously dispersible bacteria suitable for predation of minute animals with high nutritional value. Produced. Because of the high protein content in this organic wastewater, the bacteria are rich in amino acids, and as a result, the micro-animals that prey on these bacteria also contain high amounts of amino acids.

  In the second biological treatment tank 20, micro animals are continuously cultured. At the start of culture, preferably a small amount of micro-animals are added, and in some cases, activated sludge from a food factory or the like is added, and aeration is carried out by aeration means such as a diffuser tube 21 to make DO preferably 1 mg / L or more The 1st treated water from the 1st biological treatment tank 10 is added, maintaining at 2-8 mg / L. This addition is preferably a continuous type, but may be a batch type in the initial stage. As for the 2nd biological treatment tank 20, it is desirable to maintain pH to 7-8. If the temperature of the 2nd biological treatment tank 20 is maintained at 25-30 degreeC, since it eats bacteria of the substantially same quantity as the weight of a metazoan per day, it is preferable to add 1st treated water on the basis of this.

The second biological treatment tank 20 has a constant SRT and a tank load selected from the range of a tank load of 1 to 5 kg-BOD / m ³ / day with respect to the raw water at the inlet of the main treatment apparatus for 10 to 40 days. It is preferable to supply drainage so that it becomes. The optimum tank load, SRT, varies depending on the type of drainage, especially the type of organic matter.

For example, for soluble food wastewater containing 50% of protein and sugar each, when the temperature is 25 ° C., the tank load is 4 kg / m ³ / day and SRT is about 15 days, and both the load and SRT are within about 20%. It is preferable to maintain the range.

In addition, in the case of soybean soup drainage, a tank load of 3.5 kg / m ³ / day and SRT of about 20 days is optimal, and it is preferable to maintain both the load and SRT within a range of 20% or less.

  Further, the optimum tank load, SRT, varies depending on the temperature. When the temperature rises by 10 ° C., the tank load is doubled and the SRT is about half.

  Therefore, if the water temperature is different by 20 ° C in summer and winter, the load on the second biological treatment tank 20 is doubled the annual average value in summer and half the annual average value in winter. The conditions of the tank 20 can be optimally maintained for microanimal production. The variation of the load is processed by the sub processor 3.

  If this operation is continued, the solid matter containing the micro-animal in the second biological treatment tank 20 is stabilized at a concentration of about 3 to 10 g / L in terms of dry weight. The small animal species in the tank are mainly metazoans, rotifers, and contain small amounts of Paramecium, Artemia, Daphnia and the like.

  The second treated water from the second biological treatment tank 20 is introduced into the settling tank 30 and subjected to solid-liquid separation, and the treated water is taken out of the system.

  In order to harvest metazoans, the first filter medium 41 is stretched on the upper side of the concentration tank 40, the second filter medium 42 is stretched on the lower side, and the upper side of the first filter medium 41. The sedimentation sludge in the second biological treatment tank 20 and the sedimentation sludge in the sedimentation tank 30 are introduced. The metazoans and sludge that pass through the first filter medium 41 but do not pass through the second filter medium 42 are removed from the concentration tank 40, and the metazoan-containing sludge is harvested as a feed additive raw material.

  The mesh size of the first filter medium 41 is preferably 500 to 2000 μm, particularly preferably 1000 to 1500 μm, and the mesh size of the second filter medium 42 is preferably 20 to 50 μm, particularly preferably 20 to 30 μm. Thereby, metazoan-containing sludge having a particle size of 20 to 2000 μm, particularly 50 to 500 μm, is harvested from the concentration tank 40 as an additive for feed.

  The second biological treatment tank includes a sludge having a large particle diameter that does not pass through the first filter medium 41 and a liquid containing fine sludge, disperse bacteria, metazoans, soluble organic components, and the like that have passed through the second filter medium 42. 20 is preferably returned.

  Only the sludge from the settling tank 30 may be introduced into the concentration tank 40.

  When harvesting metazoans, it is desirable to harvest so that some metazoans remain instead of the total amount. You may make it harvest only the amount which increased once a day once a day. The increased amount (weight) of metazoans is 20-40% of the weight of the given bacteria. As described above, in the first biological treatment tank 10, about 50% of the charged saccharides and proteins are converted into bacteria. Therefore, metazoans of about 10 to 20 wt% of the saccharides and proteins charged into the first biological treatment tank 10. Is produced.

A general organic wastewater treatment system can be used for the sub-treatment process. However, aerobic biological treatment using a fixed bed is preferable so that it can withstand load fluctuations (so that sludge can be retained inside the fixed bed even if the unloaded state continues for several days). As the fixed bed, a fixed bed such as biofilm filtration or immersion filter bed is desirable. If a fixed bed is used, sludge separation is less like a fluidized bed, and a large amount of sludge can be held on the surface or gap of the carrier. Since sludge is retained in the tank, the state of no load continues for several days, and even when the load is applied thereafter, the processing is not delayed. As the fixed bed carrier, porous ceramic filter media, plastic filter media and sponges are desirable so that sludge can be retained not only on the surface but also in the gaps. The aeration amount is managed so that DO is 1 to 3 mg / L. As for the tank load of a sub-process, 0-5 kg-BOD / m < ³ > / day is preferable.

In order to maintain the load of the first biological treatment tank 10 in a predetermined range, the tank load of the first biological treatment tank (dispersible bacteria production tank) 10 is a predetermined load (between 2 and ³⁰ kg-BOD / m ³ / day). The organic wastewater is supplied to the main treatment device 2 so that the load range is selected from the above, and the organic wastewater not supplied to the main treatment device 2 is supplied to the sub-treatment device 3 for processing.

In one aspect of the present invention, the TOC concentration in the pretreatment tank 1 is measured in advance, and the flow rate (design flow rate) to the first biological treatment tank 10 for the first biological treatment tank 10 to obtain a tank load in a predetermined range is set in advance. First, at the start of operation (at the time of restart), the entire amount of organic waste water from the pretreatment tank 1 is passed through the main treatment device 2 and reaches a predetermined water level. Then, during normal operation, the pretreatment tank 1 A part of the organic waste water from the water is branched to the sub-processing device 3 and the flow rate is adjusted so that the flow rate to the first biological treatment tank 10 becomes the designed flow rate, thereby reducing the tank load of the first biological treatment tank 10 to a predetermined range. It is intended to be maintained. At this time, the flow rate can be controlled by, for example, providing a flow meter and a flow rate adjusting valve in the pipe between the branch point and the first biological treatment tank 10. In addition, it is desirable that the fluctuation range of the tank load of the first biological treatment tank 10 is as small as possible, for example, maintaining within a range of about ± 50%.
As described above, the present invention aims to control the load of the main treatment apparatus 2 so that micro-animals can be stably cultured regardless of fluctuations in the raw water load. It is not supplied into the processing device 2.

  In this way, by letting the surplus load of organic matter escape to the sub-processing device 3, even if the load of the raw water fluctuates, the operating conditions of the main processing device 2 can be maintained constant, so that the stable animal A feed additive with a high content can be produced.

  The sludge containing the harvested live animals may be used as an additive for feed as it is, may be dehydrated to be used as an additive for feed, or may be dried and used as an additive for feed. In addition, other additives may be added. Examples of other additives include vitamins, minerals, antibiotics, food additives, and the like.

  A mixed feed is produced by mixing the feed additive produced by the method of the present invention with a feed such as fish meal. A preferable blending amount of the feed additive in the mixed feed is 0.5 to 40 wt%, particularly 1 to 20 wt% in a state where the mixed feed is dried at 105 ° C. until reaching a constant weight.

  As feed, 1 type (s) or 2 or more types, such as fish meal, grains, soybeans, gluten meal, wheat flour, feed yeast, and fats and oils, can be used.

<Example 1>
According to the flow of FIG. 1, microanimals were cultured using raw fish water as raw water under the following conditions, and metazoan-containing sludge was harvested. The first filter medium 41 has a mesh of 1000 μm, and the second filter medium has a mesh of 20 μm. The entire amount of the sludge that did not pass through the first filter medium 41 and the liquid that passed through the second filter medium 42 was returned to the second biological treatment tank 20.

The oil and SS in the raw water were removed in the pretreatment tank 1. In this embodiment, the flow rate of the raw water supply is controlled so that the tank load of the first biological treatment tank is maintained at about 28 kg-BOD / m ³ / day, and the surplus raw water is branched to the sub-treatment device 3. Liquid was sent. The raw water was a protein waste liquid that had a high load but was easily degradable and could be treated with this apparatus.

Raw water (organic wastewater):
Fish soup drainage containing 50 wt% protein, 30 wt% carbohydrates, and 10 wt% crude fat The raw water concentration varies between 1 and 2 kg-BOD / m ³ , and the raw water amount varies between 10 and 15 m ³ / hr.
Agitation strength G value: 5 s ⁻¹
DO: 2 mg / L
Temperature: 27 ° C
Tank capacity: 8.5m ³
Second biological treatment tank 20
DO: 2 mg / L
Temperature: 27 ° C
Tank capacity: 120m ³
Sub-processing device 3
DO: 2 mg / L
Temperature: 27 ° C
Fixed bed: 40% plastic filter medium added to the tank volume Tank capacity: 160 m ³

After harvesting in the concentration tank 40, live animal-containing sludge was collected, dehydrated to 90 wt% with a centrifugal dehydrator, and dried to a constant weight at 105 ° C. A portion of this dried sludge was collected, metazoans were taken out, and the content of minute animals was measured. As a result, it was 10 wt% with respect to the dried sludge.
On the other hand, although the raw water load greatly fluctuated in the sub-treatment device 3, the activated sludge treatment was strong against the load fluctuation, so that the treated water was stably obtained by absorbing the load fluctuation.

<Comparative Example 1>
As shown in FIG. 2, metazoans were cultured using the same raw water in the same flow as in Example 1 except that the pretreatment means 1 and the sub-treatment device 3 were omitted.

In this comparative example 1, the tank load of the first biological treatment tank 10 was an operating condition that exceeded 6 kg-BOD / m ³ / day.

  A portion of the sludge containing fine organisms harvested under these operating conditions was collected, dehydrated to 90 wt% or less with a centrifugal dehydrator, and dried at 105 ° C. to a constant weight. A portion of this dried sludge was collected and the metazoan content was measured. As a result, it was almost 0% with respect to the dried sludge, resulting in an unsuitable harvest as a feed material.

<Comparative Example 2>
As shown in FIG. 2, the sub-treatment device 3 in FIG. 1 is replaced with the main treatment device 2a, and the same treatment device is provided in two series, except that raw water is passed at an equal flow rate in each series. Microanimals were cultured under conditions equivalent to 1, and metazoan-containing sludge was harvested.

Raw water (organic wastewater):
Fish soup drainage containing protein 50 wt%, carbohydrate 30 wt%, crude fat 10 wt% Raw water concentration varies between 1-2 kg-BOD / m ³ and raw water amount varies between 10-15 m ³ / hr. 10a
Agitation strength G value: 5 s ⁻¹
DO: 2 mg / L
Temperature: 27 ° C
Tank capacity: 8.5m ³
Second biological treatment tank 20, 20a
DO: 2 mg / L
Temperature: 27 ° C
Tank capacity: 120m ³

  In Comparative Example 1, since the raw water load is simply distributed in two series, both the tank loads of the first biological treatment tanks 10 and 10a fluctuated. As a result, the live animal-containing sludge collected in the concentration tanks 40 and 40a was collected, dehydrated to 90 wt% with a centrifugal dehydrator, and dried at 105 ° C. until a constant weight was obtained. A portion of this dried sludge was collected, metazoans were taken out, and the microanimal content was measured. As a result, it was almost 0 wt% with respect to the dried sludge, and it became an unsuitable harvest as a feed material.

  From the above examples and comparative examples, it can be seen that according to the present invention, micro-animals can be cultured stably even when the concentration of raw water and the amount of water vary greatly.

DESCRIPTION OF SYMBOLS 1 Pre-processing means 2, 2a Main processing apparatus 3 Sub-processing apparatus 10, 10a 1st biological treatment tank 20, 20a 2nd biological treatment tank 21, 21a Aeration pipe 30, 30a Precipitation tank 40, 40a Concentration tank 41, 41a 1st Filter media 42, 42a Second filter media

Claims (6)

A first biological treatment step of introducing an organic wastewater into a first biological treatment tank to obtain a first biological treatment liquid containing dispersible bacteria by aerobic biological treatment with bacteria;
A second biological treatment step of introducing the first biological treatment liquid into the second biological treatment tank and treating the activated sludge to obtain a second biological treatment liquid;
In a method for producing a feed additive by a main treatment step having a sludge separation step of taking out a part of the sludge in the tank of the second biological treatment tank and obtaining it as a feed additive,
A method for producing an additive for feed, characterized in that at least a part of the organic waste water is supplied to the sub-treatment process for treatment so that the tank load of the first biological treatment tank falls within a predetermined range. In Claim 1, the tank load of a 1st biological treatment tank is the load range selected from 2-30 kg-BOD / m < ³ > / day, The production method of the additive for feed characterized by the above-mentioned.   3. The method for producing an additive for feed according to claim 1 or 2, further comprising a pretreatment means for removing solids and / or oils in the organic waste water in the first stage of the first biological treatment tank. The sub-treatment step according to any one of claims 1 to 3, wherein the sub-treatment step is an aerobic biological treatment using a fixed bed, and the tank load is 0 to 5 kg-BOD / m ³ / day or less. Production method of feed additives. 5. The sludge retention time of the second biological treatment tank in the second biological treatment step is 10 to 40 days in any one of claims 1 to 4, and the tank load is relative to the raw water at the inlet of the first biological treatment tank. Is 1-5 kg-BOD / m < ³ > / day, The production method of the additive for feed characterized by the above-mentioned. A first biological treatment tank that receives organic wastewater and aerobic biological treatment with bacteria to obtain a first biological treatment liquid containing dispersible bacteria;
A second biological treatment tank for receiving the first biological treatment liquid and treating the activated sludge to obtain a second biological treatment liquid;
In the apparatus for producing the feed additive by the main treatment apparatus having the sludge separation means for taking out a part of the sludge in the tank of the second biological treatment tank and obtaining it as the feed additive,
A feed additive production apparatus comprising a sub-treatment device that receives and treats at least a portion of organic waste water so that the tank load of the first biological treatment tank falls within a predetermined range.

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